wordclock/src/matrix/render_functions.cpp

#include <Arduino.h>
#include "render_functions.h"
#include "led_matrix.h"
#include "udp_logger.h"

extern LEDMatrix led_matrix;

const String clock_chars_as_string = "ESRISTNFUNFVIERTELZEHNZWANZIGHVORPIKACHUNACHHALBMELFUNFMITTERNACHTEINSUWUZWEIDREIFUNVIERSECHSOBACHTSIEBENZWOLFZEHNEUNEUHR";

/**
 * @brief control the four minute indicator LEDs
 *
 * @param minutes minutes to be displayed [0 ... 59]
 * @param color 24bit color value
 */
void draw_minute_indicator(uint8_t minutes, uint32_t color)
{
    // separate LEDs for minutes in an additional row
    switch (minutes % 5)
    {
    case 1:
    {
        led_matrix.set_min_indicator(0b1000, color);
        break;
    }

    case 2:
    {
        led_matrix.set_min_indicator(0b1100, color);
        break;
    }

    case 3:
    {
        led_matrix.set_min_indicator(0b1110, color);
        break;
    }

    case 4:
    {
        led_matrix.set_min_indicator(0b1111, color);
        break;
    }
    case 0:
    default:
    {
        break;
    }
    }
}

/**
 * @brief Draw the given sentence to the word clock
 *
 * @param message sentence to be displayed
 * @param color 24bit color value
 * @return int: 0 if successful, -1 if sentence not possible to display
 */
int show_string_on_clock(String message, uint32_t color)
{
    String word = "";
    int last_letter_clock = 0;
    int word_position = 0;
    int idx = 0;

    // add space on the end of message for splitting
    message = message + " ";

    // empty the target grid
    led_matrix.flush();

    while (true)
    {
        // extract next word from message
        word = split(message, ' ', idx);
        idx++;

        if (word.length() > 0)
        {
            // find word in clock string
            word_position = clock_chars_as_string.indexOf(word, last_letter_clock);

            if (word_position >= 0)
            {
                // word found on clock -> enable leds in targetgrid
                for (unsigned int i = 0; i < word.length(); i++)
                {
                    unsigned int x = (word_position + i) % MATRIX_WIDTH;
                    unsigned int y = (word_position + i) / MATRIX_WIDTH;
                    led_matrix.grid_add_pixel(x, y, color);
                }
                // remember end of the word on clock
                last_letter_clock = word_position + word.length();
            }
            else
            {
                // word is not possible to show on clock
                return -1;
            }
        }
        else // end - no more word in message
        {
            break;
        }
    }

    return 0; // return success
}

/**
 * @brief Converts the given time as sentence (String)
 *
 * @param hours hours of the time value
 * @param minutes minutes of the time value
 * @return String time as sentence
 */
String time_to_string(uint8_t hours, uint8_t minutes)
{
    String message = "ES IST "; // first two words

    // show minutes
    if (minutes >= 5 && minutes < 10)
    {
        message += "FUNF NACH ";
    }
    else if (minutes >= 10 && minutes < 15)
    {
        message += "ZEHN NACH ";
    }
    else if (minutes >= 15 && minutes < 20)
    {
        message += "VIERTEL NACH ";
    }
    else if (minutes >= 20 && minutes < 25)
    {
        message += "ZWANZIG NACH ";
    }
    else if (minutes >= 25 && minutes < 30)
    {
        message += "FUNF VOR HALB ";
    }
    else if (minutes >= 30 && minutes < 35)
    {
        message += "HALB ";
    }
    else if (minutes >= 35 && minutes < 40)
    {
        message += "FUNF NACH HALB ";
    }
    else if (minutes >= 40 && minutes < 45)
    {
        message += "ZWANZIG VOR ";
    }
    else if (minutes >= 45 && minutes < 50)
    {
        message += "VIERTEL VOR ";
    }
    else if (minutes >= 50 && minutes < 55)
    {
        message += "ZEHN VOR ";
    }
    else if (minutes >= 55 && minutes < 60)
    {
        message += "FUNF VOR ";
    }

    // increment hour when 25 minutes of an hour have passed
    if (minutes >= 25)
    {
        hours++;
    }

    // convert hours to 12h format
    if (hours > 12) // 24h -> 12h, except 12h
    {
        hours -= 12;
    }

    // show hours
    switch (hours)
    {
    case 0:
        if (minutes >= 0 && minutes < 5)
        {
            message += "MITTERNACHT ";
        }
        else
        {
            message += "ZWOLF ";
        }
        break;
    case 1:
        message += "EIN";
        // EIN(S)
        if (minutes > 4)
        {
            message += "S";
        }
        message += " ";
        break;
    case 2:
        message += "ZWEI ";
        break;
    case 3:
        message += "DREI ";
        break;
    case 4:
        message += "VIER ";
        break;
    case 5:
        message += "FUNF ";
        break;
    case 6:
        message += "SECHS ";
        break;
    case 7:
        message += "SIEBEN ";
        break;
    case 8:
        message += "ACHT ";
        break;
    case 9:
        message += "NEUN ";
        break;
    case 10:
        message += "ZEHN ";
        break;
    case 11:
        message += "ELF ";
        break;
    case 12:
        message += "ZWOLF ";
        break;
    }
    if ((minutes < 5) && (hours != 0))
    {
        message += "UHR ";
    }

    return message;
}

/**
 * @brief Splits a string at given character and return specified element
 *
 * @param s string to split
 * @param parser separating character
 * @param index index of the element to return
 * @return String
 */
String split(String s, char parser, int index)
{
    String rs = "";
    int parser_cnt = 0;
    int r_from_index = 0, r_to_index = -1;

    while (index >= parser_cnt)
    {
        r_from_index = r_to_index + 1;
        r_to_index = s.indexOf(parser, r_from_index);
        if (index == parser_cnt)
        {
            if (r_to_index == 0 || r_to_index == -1)
            {
                return "";
            }
            return s.substring(r_from_index, r_to_index);
        }
        else
        {
            parser_cnt++;
        }
    }
    return rs;
}